So how are they gonna ruin Obi-Wan?

Obi Wan has shown to be fairly level-headed and competent since his early-mid twenties, thanks to the Prequels, so I think a standalone film won't happen for him because his character wouldn't be able to be shown as needing a racial minority, SJW Droid, and a woman to prop him up. If he had a standalone film, he'd be a Strong Male Lead (tm) and we can't have that!

Obi-Wan will announce that he is a woman living in a man's body and he only fled to Tatooine because of persecution by the homophobes in the Empire.

He's a clone!

Obi-Wan will do a series of YouTube videos where he criticizes the overuse of Jedi tropes in video games. Sith lords from around the galaxy will start their own channels and gain ad revenue solely off of criticizing Obi-Wan's criticism. Later on in the film, the most popular YouTuber, Jar Jar Binks, makes a video containing a racist joke. The galaxy panics as advertisers pull their ads from all videos.

-He'll fall in love with Uncle Owen

-He'll reveal himself to be pansexual

-He'll be outshone by a token female sidekick character who will hog his limelight, make him look stupid and incompetent and make him look like a weak man (this is the most likely scenario)

A lonesome down on his luck Jedi Knight finds not only love but also redemption as Academy Award
Nominee™ Obi-Wan Kenobi slowly falls for the charms of the dashing Savage Opress – the brother of Darth Maul!

Together they fight not only the Sith but homophobia too! Directed by Paul Feig with Ewan McGregor in the title role and co-starring Melissa McCarthy, Rosie O'Donnell, George Clooney as Batman and Whoopi Goldberg as herself!

They’ll explore the oppression that sand people have to endure from an evil white CIS male Jedi. A powerful female character will beat the crap out of Obi-Wan. Obi-Wan will have a relationship with this powerful female but she will end up cucking Obi-Wan with a Sith Jawa.

They will find a way, somehow. They seem committed to fucking Star Wars up beyond repair.